EP 1 283 325 A1 discloses a gas turbine blade with an aerodynamically profiled blade leaf which is assembled from two shell elements. The two shell elements are firmly connected to one another along their longitudinal extent, on the inflow-edge side and on the outflow-edge side, by means of a high-pressure and high-temperature bonding process.
The known prior art has the disadvantage that the bonding connection of the longitudinally slotted blade leaf may possibly come loose in the region of the leaf tip and therefore the two individual shells may come apart during operation. This leads to flow losses during operation. Moreover, in individual instances, there is the risk that the two shell elements may come loose from one another completely and cause serious secondary damage in the turbine.
Furthermore, U.S. Pat. No. 3,899,267 discloses a closing insert for a blade leaf tip of a moving blade which is inserted in the region of the blade tip between the two side walls forming the blade leaf. In this case, the closing insert having a C-shape cross section is seated in two mutually opposite pockets which are provided in each case on the inside of the respective blade leaf wall. In order to protect the closing insert against loss, projections on the insides are provided which absorb the centrifugal forces acting on the closing insert.